Move notification resource loading from content/child to blink

third_party/WebKit/Source/modules/notifications/NotificationImageLoader.cpp

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "modules/notifications/NotificationImageLoader.h"
+
+#include "core/dom/ExecutionContext.h"
+#include "core/fetch/ResourceLoaderOptions.h"
+#include "platform/image-decoders/ImageDecoder.h"
+#include "platform/image-decoders/ImageFrame.h"
+#include "platform/network/ResourceError.h"
+#include "platform/network/ResourceLoadPriority.h"
+#include "platform/network/ResourceRequest.h"
+#include "platform/weborigin/KURL.h"
+#include "public/platform/WebURLRequest.h"
+
+namespace blink {
+
+NotificationImageLoader::NotificationImageLoader()
+    : m_isStopped(false)
+    , m_data(SharedBuffer::create())
+{
+}
+
+NotificationImageLoader::~NotificationImageLoader()
+{
+}
+
+void NotificationImageLoader::start(
+    ExecutionContext* executionContext,
+    const KURL& url, PassOwnPtr<ImageCallback> imageCallback)
+{
+    if (m_isStopped)

[Peter Beverloo, 2016/04/13 18:32:27]

I don't think we'll ever hit this case unless someone calls start() multiple
times?

    DCHECK(!m_isStopped);

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Done.

+        return;
+
+    m_imageCallback = imageCallback;
+
+    // TODO(mvanouwerkerk): Add a timeout mechanism: crbug.com/579137.

[Peter Beverloo, 2016/04/13 18:32:27]

Should we have a TODO on adding a FetchInitiatorTypeName for notifications?

[Peter Beverloo, 2016/04/13 18:32:27]

Note: While I'm sure you're aware, ThreadableLoaderOptions has a `timeout`
member that should make this much easier now.

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Sure... what is it used for?

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Yeah that's why it's here. I'm not sure we have enough data yet to pick a useful
timeout.

[Peter Beverloo, 2016/04/15 11:07:29]

I assume for DevTools' Initiator column in the network tab when no source
file/line are available.

+    ThreadableLoaderOptions threadableLoaderOptions;
+    threadableLoaderOptions.preflightPolicy = PreventPreflight;

[Peter Beverloo, 2016/04/13 18:32:27]

To confirm: We prevent pre-flight requests since we're allowing cross-origin
requests and thus don't need CORS checks, which is OK because they're images,
right?

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Acknowledged.

+    threadableLoaderOptions.crossOriginRequestPolicy = AllowCrossOriginRequests;
+
+    ResourceLoaderOptions resourceLoaderOptions;
+    resourceLoaderOptions.allowCredentials = AllowStoredCredentials;
+    if (executionContext->isWorkerGlobalScope())
+        resourceLoaderOptions.requestInitiatorContext = WorkerContext;
+
+    ResourceRequest resourceRequest(url);
+    resourceRequest.setRequestContext(WebURLRequest::RequestContextImage);
+    resourceRequest.setPriority(ResourceLoadPriorityMedium);
+    resourceRequest.setRequestorOrigin(executionContext->getSecurityOrigin());
+
+    m_threadableLoader = ThreadableLoader::create(*executionContext, this,

[Peter Beverloo, 2016/04/13 18:32:27]

micro nit: nowrap

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Done.

+        threadableLoaderOptions, resourceLoaderOptions);
+    m_threadableLoader->start(resourceRequest);
+}
+
+void NotificationImageLoader::stop()
+{
+    if (m_isStopped)
+        return;
+
+    m_isStopped = true;
+    if (m_threadableLoader) {
+        m_threadableLoader->cancel();
+        // WorkerThreadableLoader keeps a Persistent<WorkerGlobalScope> to the
+        // ExecutionContext it received in |create|. Kill it to prevent
+        // reference cycles involving a mix of GC and non-GC types that fail to
+        // clear in ThreadState::cleanup.
+        m_threadableLoader.clear();
+    }
+}
+
+void NotificationImageLoader::didReceiveData(const char* data, unsigned length)
+{
+    m_data->append(data, length);
+}
+
+void NotificationImageLoader::didFinishLoading(unsigned long resourceIdentifier,

[Peter Beverloo, 2016/04/13 18:32:27]

micro nit: nowrap

[Michael van Ouwerkerk, 2016/04/14 13:42:11]

Done.

+    double finishTime)
+{
+    // If this has been stopped it is not desirable to trigger further work,
+    // there is a shutdown of some sort in progress.
+    if (m_isStopped)
+        return;
+
+    OwnPtr<ImageDecoder> decoder = ImageDecoder::create(*m_data.get(),
+        ImageDecoder::AlphaPremultiplied,
+        ImageDecoder::GammaAndColorProfileApplied);
+    if (decoder) {
+        decoder->setData(m_data.get(), true /* allDataReceived */);
+        // The |ImageFrame*| is owned by the decoder.
+        ImageFrame* imageFrame = decoder->frameBufferAtIndex(0);
+        if (imageFrame) {
+            (*m_imageCallback)(imageFrame->bitmap());
+            return;
+        }
+    }
+    runCallbackWithEmptyBitmap();
+}
+
+void NotificationImageLoader::didFail(const ResourceError& error)
+{
+    runCallbackWithEmptyBitmap();
+}
+
+void NotificationImageLoader::didFailRedirectCheck()
+{
+    runCallbackWithEmptyBitmap();
+}
+
+void NotificationImageLoader::runCallbackWithEmptyBitmap()
+{
+    // If this has been stopped it is not desirable to trigger further work,
+    // there is a shutdown of some sort in progress.
+    if (m_isStopped)
+        return;
+
+    (*m_imageCallback)(SkBitmap());
+}
+
+} // namespace blink